Walmart continues to offer the Stanley FatMax 140-watt Power Inverter, model no. PCI140, bundled with a Freestanding Keychain LED Light for $17.98. Opt for in-store pickup to dodge the $5.99 shipping charge. That's tied with our mention from last week as the best deal we've seen. (It's also at least $5 less than you'd pay for just the inverter elsewhere.) It plugs into your car's DC power outlet and features a 1-amp USB port, two AC outlets, 3-foot cable, and mounting kit.